Synthesis of some erbium(Ⅲ) chelates and characterization of their NIR emission properties for use in organic near infrared optical amplification waveguides

摘要

Recent years have seen considerable interest in the possibility of using rare earth chelates as emissive materials in organic media. Lanthanides luminescence is quite interesting in applications requiring high spectral purity (for example in OLEDs), or infra red luminescence, in active optical waveguides for telecommunications. The use of organic optical amplification modules is attractive for their ease of fabrication, and therefore their potential low cost, but the high losses at NIR wavelength and the limitation of the emission lifetime due to the quenching effect of the organic matrix greatly limits their performances. However, rare earth chelates offer the possibility to reduce by several orders of magnitude the pump power needed for population inversion, using the absorption of the organic ligand followed by an energy transfer to the rare earth ion. By choosing a ligand with a high molecular absorption, it should then be possible to balance the short emission lifetime and hence-to obtain optical amplification. We report on the synthesis and characterisation of the optical near infrared properties of an erbium phthalocyanine. The complex shows very high absorption in the 670nm region, is highly soluble and shows minimum concentration quenching effect. The red absorption could allow the use of standard laser diode as pump source in a planar polymer amplifier device.